645168742 has 8 divisors (see below), whose sum is σ = 1001124000. Its totient is φ = 311460744.

The previous prime is 645168707. The next prime is 645168749. The reversal of 645168742 is 247861546.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (645168749) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5561742 + ... + 5561857.

It is an arithmetic number, because the mean of its divisors is an integer number (125140500).

Almost surely, 2^645168742 is an apocalyptic number.

645168742 is a deficient number, since it is larger than the sum of its proper divisors (355955258).

645168742 is a wasteful number, since it uses less digits than its factorization.

645168742 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11123630.

The product of its digits is 322560, while the sum is 43.

The square root of 645168742 is about 25400.1720860312. The cubic root of 645168742 is about 864.0875995358.

The spelling of 645168742 in words is "six hundred forty-five million, one hundred sixty-eight thousand, seven hundred forty-two".